1. Field of the Invention
The present invention relates to remote controlled systems for motor vehicles, and more particularly, to a remote control device that safely controls the opening and closing of a vehicle window using a two-way communication link.
2. Description of Related Art
Remote control devices are widely used with motor vehicles for a variety of purposes, such as to arm/disarm security systems, to lock/unlock doors, and to unlatch the hood and/or trunk. A typical remote control device communicates encoded radio frequency (RF) signals to a processing unit disposed within the vehicle to command the execution of different functions within the vehicle. The remote control device may be small enough to serve as a key fob for holding the user's car keys, and may include a plurality of buttons associated with each of the functions controlled by the remote control device. The processing unit is generally adapted to emit an audible feedback signal in the form of a chirp to confirm successful completion of a desired function, e.g., arming of the vehicle security system.
One potential application for a remote control device is to command the opening and closing of a vehicle window from a remote location. For example, a user may want to open the vehicle windows before entering the vehicle, especially when the vehicle has become hot from sitting in direct sunlight. Conversely, a user may want to close the vehicle windows from a remote location, such as in response to a sudden rain storm. An example of a remote vehicle window control system is provided in U.S. Pat. No. 4,467,249, to Swearingen, Jr.
Notwithstanding the potential advantages of such a capability, remote control window opening/closing systems such as disclosed by Swearingen, Jr. have significant disadvantages that have prevented them from achieving commercial acceptance. Most significantly, there is an inherent safety risk attendant with such remote window operation, as a motor powered window can potentially cause harm to objects that are caught within the open window as the window closes. Even when this particular risk of harm is not present, the user cannot confirm successful completion of a remote window operation without directly observing the operation of the vehicle window. Such observation generally requires the user to be close enough to the vehicle so as to diminish the advantage of remote control operation.
Another disadvantage of the conventional vehicle remote control devices is that the chirp that serves as the audible feedback signal from the processing unit is often unnecessarily obtrusive. The chirp must necessarily be loud enough for the user to hear from a location somewhat distant from the vehicle. In addition, the volume of the chirp is often intentionally selected to be very high so as to serve as a warning to potential vehicle intruders of the presence of the security system. Nevertheless, the prevalence of vehicle security systems in urban areas has significantly diminished the deterrent effect of the chirp. More typically, the loud chirp constitutes a source of annoyance to the vehicle user's neighbors, and can be startling to pedestrians that pass near the vehicle when the chirp occurs.
Thus, it would be desirable to provide a remote control device that can be safely used to open and close vehicle windows while preventing the risk of harm to objects present in the open window. It would be further desirable to provide direct feedback of the remote controlled window operation and status to the user in a discrete manner through the remote control device.